The present invention relates to security gates to restrict movements of infants and small children through access ways, such as doorways and hallways leading to restricted areas of the home, stairways, or the like.
Child security gates must function as an impassible barrier to exclude passage of an infant or child through the accessway, but it is also necessary to provide for removal of the barrier to permit passage by an attending adult. Accordingly, a number of gate designs have been developed that allow for barrier removal, for example by collapsing the gate, pivoting the gate out of the access way, or removing the gate entirely from the access way.
In addition to providing a removable barrier that permits adult access, it is also desirable to provide a gate that is adaptable for installation in a variety of differently dimensioned access ways, and which may also be transferred from one access way to another to accommodate daily movements of the child and attending adult.
Various designs have been developed that address one or more of the above needs. For example, child safety gates have been designed that can be extended and retracted in a number of ways, to provide a removable barrier function and/or allow adjustable placement of the barrier to block differently dimensioned access ways. One conventional design provides a collapsible lattice gate that can be extended across an access way to provide a barrier or collapsed to allow adult passage. Examples of this type of gate are described in U.S. Pat. No. 4,723,587, issued to Scruggs, Jr. on Feb. 9, 1988, and in U.S. Pat. No. 4,669,521 issued to Barnes et al. on Jun. 2, 1991.
Another type of gate forms a barrier consisting of two or more partitions that slide relative to one another along tracks, slots or horizontally disposed rods. These gates can be expanded to occupy the entire width of the access way, or retracted to permit adult passage (either by collapsing, pivoting or removing the gate from the access way). One example of this general design is described in U.S. Pat. No. 4,831,777 issued to Johnson, Jr. on May 23, 1989.
Most sliding panel gates are installed and disengaged using a friction mounting mechanism, which typically incorporates spring biased telescoping rods or pistons with engagement feet that exert outward pressure to frictionally engage one or both sides of the access way. Such friction mounted barriers are removed by compressing the biasing spring to retract the rods or pistons, either manually or through a lever mechanism. Examples of safety gates employing various aspects of these design features are disclosed for example in U.S. Pat. No. 5,272,840 issued to Knoedler et al., on Dec. 28, 1993; 360,191; U.S. Pat. No. 4,492,263 issued to Gebhard; and U.S. Pat. No. 5,367,829 issued to Abrams et al. on Nov. 29, 1994.
While the above described safety gates are generally satisfactory for preventing passage of infants or small children through access ways, a number of shortcomings of such devices have been identified by the inventor. For example, although friction mounted gates permit rapid installation and removal, and avoid undesirable installation of mounting hardware in the access way, these gates are generally less stable than permanently installed gates (i.e. collapsible or pivoting gates mounted by fixed hinges, mounts and/or latches). More specifically, because these gates rely on friction mounting to secure the gate between the sides of the access way, a child may purposefully or accidentally apply sufficient force to knock the engagement feet loose, causing the gate to fall out of place. This problem may be exacerbated with conventional, spring biased mounting designs after long periods of use if biasing springs become fatigued and incapable of exerting sufficient force on the sides of the access way to prevent undesired dislodgement.
At least one existing safety gate partially ameliorates the problem of unreliable friction mounting, as disclosed in U.S. Pat. No. 5,367,829 issued to Crossley et al. on Nov. 29, 1994. In this two-panel gate design, paired bumpers on each side of the gate are brought into close juxtaposition with opposing sides of the access way by sliding the panels to increase their combined width to approximately fill the access way. The bumpers on one side are then lockably extendable by a camming mechanism rather than a spring, so that the gate is secured in a tighter friction fit within the access way.
This latter design suffers its own disadvantages, however, particularly in terms of its potential instability when used in access ways that feature unequal widths between the sides of the access way at heights corresponding to the upper and lower bumper positions. For example, if the access way is narrower adjacent the lower bumper than adjacent the upper bumper, engagement of the lower bumper with the side of the access way will limit extension of the upper bumper so that it does not tightly engage the access way. Accordingly, when an infant or child pushes or falls against the gate, the gate may become dislodged and allow passage of the child to a restricted area.
In view of the above, there is a need in the art for a child safety gate that more conveniently and reliably excludes passage of infants and small children through restricted access ways.